Mixed boot disks within a cluster

Just a quick question to see if anyone's encountered any issues with this setup.

We have 10 legacy hosts (HP BL660s) running ESXi 6.5, booting from local USB drives. These hosts were identified as venerable to the ESXiArgs exploit and were scheduled to be patched.

During the patching process, read errors were detected on some of the hosts and the upgrade failed.
These hosts will most likely need to be rebuilt, on reliable disk.

We have the option this time of using boot from SAN, rather than internal USB disks.

My questions are;

1. Has anyone encountered issues with "mixed mode" boot disks within a cluster? Can we have some of the host boot via SAN, while leaving the remainder on USB boot?

2. These servers are hosting Oracle DB servers. Has anyone encountered any reason why using boot from SAN for such hosts would be problematic?

Appreciate any insights or advice the community might have.